This invention relates to image labeling. More particularly, the invention relates to the labeling of orthogonal images.
An imaging system uses, among others, electromagnetic radiation, x-rays, sonic waves, or photonic energy to produce images of a target body, such as a human patient. The images produced by the imaging system provide views of the target body at various planes extending through the target body. For many applications, a primary image is taken along one plane, and corresponding secondary images are taken at multiple planes extending orthogonal to the primary image.
The imaging system also includes a computer or network of computers to store, manage, display, and retrieve the images. The computers may be part of an image management system, such as a picture archiving and communications system (PACS). To aid in the application of the images for diagnosis, analysis, and the like, the imaging system may allow the images to be labeled (annotated) by a technician, physician, or other user. Labeling is typically accomplished using an input device to indicate a point on a displayed image and to input or select the appropriate label (notation) to be displayed at the indicated point. The label appears on the displayed image, and is associated with the image in computer memory such that when the image is retrieved at a later time, the label appears on the displayed image. Where the label is made on the primary image, it is often required that a label appear on the secondary image associated with the point on the primary image selected by the pointing device. This allows the label to act as a point of reference between the two images.
One example of such annotation is known as “spine labeling”, which is the act of placing a text annotation near a vertebra of an imaged human spine. In the imaging of the human spine, a primary image may be taken in the sagittal plane (looking from the left or right side of the body), and one or more series of secondary images may be taken in the axial plane (looking from above the head or below the feet). Each series of secondary images contains a plurality of secondary images. Spine labeling includes placing a label near a vertebra of an imaged spine to serve as a point of reference for anyone viewing the image. The same label is also placed on the secondary image including the vertebra in each series of secondary images. Typically, such labels are used before neurosurgery or orthopedic surgery, for radiation therapy planning, and for interventional radiological procedures.
The annotation of orthogonal images can be time consuming. The person performing the annotation must label the primary image as well as the appropriate secondary image in each series. Care must be taken to ensure that the labels are placed consistently in each of the images.